This invention relates to non-oscillating rotary-brush type electric toothbrushes having handle integrated battery, motor, gear-reduction, and electrical-control members arranged thereto; and more particularly it relates to such units having radial-brush elements, and specifically to such devices capable of brushing a substantial number of one's teeth in one motion of the user's hand. Accordingly, while there is no known brush invention of this sort which can facilitate brushing of the entire dental array in a single "one shot" manner, the following discussion addresses the most relevant related invention art known.
Beginning then with U.S. Pat. No. 3,447,178 (filed January/1968), a pistol-grip configuration is shown having a cylindrically formed distally positioned radial-brush member, plus a special toothpaste injector means. In retrospect however, it's primary virtue appears to lay in it's early approach to more extensive brushing of either the jaw or cranial dental array in one insertion/motion; albeit less than ideally human-engineered.
Next, U.S. Pat. No. 3,551,932 endeavors to provide an electrically reversible radial-brush wherein is included a snap-apart shaft support-housing, for ease of cleaning. In U.S. Pat. No. 3,829,922 (filed January/1973) we see where this inventor has provided a special automatic reversing-switch mechanism, wherein FIG. 8 shows how the switch enables the inside and outside of the teeth/gum surfaces to be thus more effectively brushed away from the gum and up upon the teeth, so as to act to draw foreign matter out of the gum crevices interjacent to the teeth.
Perhaps most significantly, U.S. Pat. No. 3,924,841 (filed March/1974) introduced a toothbrush having a driving mechanism geared to a plurality of six coacting radial type rotary-brushes capable of brushing outward from the root area of either the jaw or the cranial teeth. These six brushes are hence geared to a motor-pinion & ring arrangement, so as to thereby stem off toward the right and left lateral sides in a rather Y-shaped formation; the battery, motor, and gear-housing being at the base of this arrangement. Critical to this layout is the need for a relatively rigid supporting structure, which is not at all really addressed in this invention disclosure. Thus, it is believed the difficulty of providing a suitable non-bulky bifurcated supporting-structure was apparently never actually revealed; hence, accounting for such a product never known to appear on the marketplace as a viable dental-care instrument.
Later, U.S. Pat. No. 4,313,237 (filed March/1980) revealed a drive related to the previous example, although somewhat less dynamic an implementation; since instead of brushing the entire jaw or cranial dental array simultaneously, the triad rotary-brush assembly is an entity in of itself, wherein FIG. 6 demonstrated the same brushing action set forth in FIG. 3 of the previous identified patent, as well as a still earlier example of U.S. Pat. No. 2,628,377 (issued February/1953).
Several other newer radial type rotary-brush patent examples have since issued to the present moment, yet they are essentially all of the single rotating-brush element design, stressing use of substantial manual dexterity by the user in determining both the extent of time-dwell needed in the different dental areas of the mouth, and the proper positioning of the brushing instrument in order to achieve optimal cleaning action.
Accordingly, this instant disclosure now intends to reveal how a fully automated arrangement of radial/rotary-brush elements may be regarded as advancement over the known invention art of record. Presently, this subject invention is being developed under auspices of the Xplak-toothbrush Co., San Diego, Calif.